The Loretto Chapel in Santa Fé, New Mexico has attracted 250,000 visitors annually due to the mysterious staircase built there in the late 19th century. When the chapel was completed, the nuns discovered they had no way to access the second level. After 9 days of prayer to St. Joseph, a carpenter appeared and constructed a spiral staircase without nails or a central support post in just one day. The identity of the carpenter was never discovered and the wood used does not exist locally, adding to the belief it was a miracle from St. Joseph. The staircase remains an architectural marvel as engineers cannot explain its structural integrity without supports.